Const vs. readonly vs. static readonly in C# .NET

Here are the differences between C# .NET const, readonly and static readonly fields. Constants: Static by default Must have compilation-time value (i.e.: you can have "A"+"B" but cannot have method calls) Can be used in attributes Are copied into every assembly that uses them (every assembly gets a local copy of values) Could be declared within functions The compiler performs some optimization by not declaring any stack space for the field